What is the context of these claims? I don't really see why either of them would be necessary.
They are necessary.
For expected utility, .51v-.50v ==.01 v == .81v-.80v
When evaluating the strength of evidence, 50% is 0dB, 51% is 0.17dB (diff 0.17dB), 80% is 6.02dB, and 81% is 6.30dB (diff 0.28dB).
Please offer a correction if I've made a mistake there.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.